When facial muscles move, they will repeatedly squeeze the skin and produce various textures. For example, when laughing, muscles will repeatedly squeeze the skin at the end of the eyes, and anxious and bored expressions can easily squeeze the skin between the eyebrows. These extruded textures are called "dynamic wrinkles". "Dynamic wrinkles" become longer and deeper with the passage of time and become "static wrinkles", which will never disappear. For example, crow's feet are fan-shaped at the end of eyes, and the head-lifting lines are horizontally distributed on the forehead.

Content source: Health News and Huaxi Biology were led by Professor Yuan, the chief physician of Shanghai Dermatology Hospital, and written by dermatologists nationwide 13.